# text = input("请输入字符串：")
# result = ""
# for i in text:
#     if i.isalpha():
#         result = result+i
#     if i.isdigit():
#         result = result+i
# max_num = 0
# max_str = ""
# for i in text:
#     num = result.count(i)
#     if num >= max_num:
#         max_num = num
#         max_str = i
# print(result)
# print(f"出现最多的字符：{max_str}，次数是：{max_num}")


# n =0
# while n != 3:
#     user = input("请输入用户名：")
#     passwd = int(input("请输入密码："))
#     if  user == "root" and passwd == 123456:
#         print("验证成功，正在登陆....")
#         break
#     elif user != "root" or passwd != 123456:
#         print("用户或密码错误，请重新输入!")
#         n+=1
#         print(f"还剩{3-n}次机会!")
# if n == 3:
#     print("验证失败，次数上限无法登录")
